Cruising Boat Safety Gear: Water Intrusion

Have you thought much about water intrusion gear on your boat? After writing about our high-water bilge alarms, I got some questions about what we carry to stop a major leak–either a failed thru-hull or a crack/hole in the hull itself.

Let’s face it: if water is coming in, it has to be stopped. Bilge pumps will quickly be overwhelmed. They can buy you some time, and they can get water out after you’ve stopped or significantly slowed the water down, but they aren’t going to save the boat by themselves.

Here are a couple of eye-opening videos showing techniques for dealing with water intrusion:

• Yachting Monthly’s Crash Test Boat is holed Part 1
• Yachting Monthly’s Crash Test Boat is holed Part 2

Simply put, some of the techniques we’ve all heard about take too long to implement . . . and some others work surprisingly well. As you watch the videos, think about the time it takes to set these up and remember that (a) they know the emergency is about to happen and (b) everything is out and ready to go.

Emergency Supplies We Carried to Stop a Leak

You can do a lot to stop water intrusion with just cushions and odd bits you find on the boat. But having a few items designed to stop leaks can come in handy, especially if you have to travel any distance before you can fix the problem.

Wood Bungs

You can push/pound soft wood plugs into a failed thru-hull (almost like a large cork) and do a good job of stopping the water. Tie one near each thru- hull (not just sea cocks) such that you can grab it quickly in an emergency.

Remember to put one on every drain and holes that are normally above the waterline, too. If the boat takes on some water, these could end up below the waterline, and you wouldn’t want water to enter here as well as in the problem areas! We have them for all thru-hulls, and a few extras besides.

You can get these from several places. If you’re ordering other things from Defender, they have good prices (shipping will eat up the savings if not part of a larger order); otherwise, Amazon has sets for both large plugs and smaller:

• Amazon set of 10 smaller plugs (1/2” to 1-1/2” max plug size – up to about 1-1/4” thru hull or hole)
• Amazon set of 9 larger plugs (holes from about 1” to 1-3/4”)
• Defender set of six plugs for holes 1/2” to 2”

Forespar Sta-Plug

This is a fairly firm yet still pliable foam plug that you can use in thru-hulls and also in larger hull breaches, including ones with irregular shapes. The base of the plug is 5” in diameter; it could probably plug holes up to 4” in diameter and slow the flow in larger odd-shaped ones (you can also use more than one to fill large holes). These have evolved since they first came on the market. An earlier version had smooth sides. The ridging on the current model makes them seal better. We had two on board. You can compress it by hand and/or twist some to insert them into holes, but it does take a bit of strength to do so.

Again, you can buy them at most marine chandleries at widely varying prices. We bought one from Defender as part of a larger order and one from Amazon when we decided we wanted a second:

• Sta-Plug on Amazon
• Sta-Plug from Defender

Hull Survivor Emergency Hull Seal

This product is a 10” diameter circle that you can deploy from inside or outside the boat to cover larger holes or cracks. The emergency hull seal uses the pressure of the water outside the hull to hold it in place. You can also tie it in place from the inside and seal it with epoxy from the outside. If you watched the first video above, it’s similar to their tying a line to a cushion and pulling it against the hull, except that this is faster to deploy, as there’s nothing to set up.

I haven’t tried it myself, but I like the idea that it’s flexible and can be rolled up and then deployed from inside the boat. We have helped save two sinking boats (when we were in the Sea of Cortez), and one of the problems with both is that it took divers to apply patches to the outside of the hull. That takes time. This seems like it’d be much faster to deploy – as well as safer (diving under a boat with wave action can cause serious head injuries).

I’ve only seen them on Amazon:

• Hull Survivor on Amazon

Splash Zone Epoxy

Splash Zone will cure underwater (or in air) and can be applied to wet surfaces with no surface preparation. You can use it on most surfaces that boats are made of – fiberglass, steel, aluminum, wood, and even cement. It is designed to be mixed by hand with “approximately equal” amounts of the two parts. Perfect for emergencies. Good for sealing a patch. I’ve seen it in action twice, where it saved a boat. It comes in several sizes; we carried a half-gallon. If you need it, you want enough.

• Splash Zone from Defender

IMPORTANT: Splash Zone comes with Part A and Part B held together with a plastic connector. Take this off before storing it. Be careful not to puncture the can! Since we bought it, the company has begun shipping it with a connector that’s easier to remove. It took Dave about 15 minutes to cut it off the product we bought. In an emergency, you want it NOW. And even the newer connector requires a screwdriver to remove it. The last thing you want to be doing is looking around for a tool in a panic.

We store all our emergency supplies in an under-the-floor storage compartment just inside the door to the cockpit. In an emergency, you want them in a very convenient place!

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